Adjustable fulcrum for lever mechanisms



March 2, 1,948. B, COPELAND 2,436,916

ADJUSTABLE FULCRUM FOR A LEVER MECHANISM Filed April l0, 1944 F/g Z irme/vif fwn/KE Carni/vp INVENTOR.

Patented Mar. 2, i948 ADJUSTABLE FULCRUM FOR LEVERr MECHANISMS Frank B. Copeland, Dayton, Ohio, assignor to The Joyce-Gridland Company, Dayton, Ohio, a corporation of Ohio Application April 1944, Serial No. 530,337

21 Claims.

This invention relates to an adjustable fulcrum for a lever mechanism and is designed more particularly for application to a lever operated lifting mechanism. m

One object of the invention is to provide a lever with a fulcrum which can be quickly' and easily adjusted to increase or decrease the distance between the same and the load on the lever in ac-` cordance with the force required to move the load.

A further object of the invention is to provide a fulcrum which can be so adjusted without disconnecting any part of the lever mechanism A lfurther object of the invention is to provide a lever mechanism in which the fulcrum is connected with a part movably supported on the lever mechanism and which isv held normally-in a iredposi'tion with relation to the lever mechanism.

A further object of the 'invention is to provide lever mechanism in which the fulcrum is connected'with a part movably supported on the socket member of the mechanism and is adjustable by a movement ofpthe lever-with relation to said socket member.

A further object of the invention is to provide such a lever mechanism in which the fulcrum may be adjusted to any desired'position within the ran-geef maximum adjustment.

.A further object of the invention is to provide such a lever mechanism which is of a strong durable construction and in which the fulcrum can be easily and positively adjusted to the desired position.

Other objects of the invention may appear as the mechanism is described in detail. In the accompanying drawings Fig. 1 is a vertical sectional view of a hydraulic lifting jack showing the invention applied thereto;Fig, 2 is a vertical sectional view taken through the lever mechanism, with the pump partly in elevation; Fig. 3 is a transverse section taken on the line 3--3 of Fig. 2; and Fig. 4 is a transverse section taken on the line 4-4 of Fig. 2. y

In these drawings I have illustrated one embodiment of my invention and have shown the same as embodied in the lever mechanism of a hydrauliclifting'jack but it will be understood that the invention may take various forms and may be applied to lever mechanisms of various kinds. V

In the preferred embodiment of the invention the lever mechanism comprises a member connected with a part to be operated and with the fulcrum, and herein called the operating member, and an actuating lever, or handle, which is usually but not necessarily detachably connected with the operating member. The fulcrum is movably supported and is connected with the operating member for movement with relation thereto toward and from the part to be operated, the connection preferably comprising a member with which the fulcrum is connected and 'which' is movable lengthwise of the operating member; This movable connecting member may be actuated in any suitable manner but I prefer that the lever, which is connected with and imparts operative movement to the operating member, shall Ibe movable with relation to th-e operatingvmember and that this movement of the lever be utilized to actuate the member with which the fulcrum is connected.

The hydraulic jack in connection with which the invention is hereillustrated, as shown in Fig. 1, comprises a base 5 on which is mounted an upright cylindricalV structure 6, provided at its upper end with a closure 'l having a central opening. Arranged within and spaced from the structure 6 is a cylinder 8 which is supported at its lower end on the base 5 andwhichextendsthroughthe opening in the closure 'l and is connected with the latter. AMounted in the cylinder 8 is a lifting element or ram 19, the lower portion l0 of which constitutes a piston and theupper portion of which projects above the cylinder 8 an-d is provided with a work engaging element ll. The spiral groove in the ram is a part of an automatic locking device which forms no part of the present invention, The space between the cylinder 8 and the cylindrical structure 6 constitutes an oil receptacle. Mounted on the base 5 exteriorly of the structure 6 .is a pump l2 comprising a, cylinder I3 and a piston I4, the upper portion of which extends above the top of the cylinder and constitutes a piston rod adapted for connection with the lever mechanism. The pump cylinder I3 is connected with the cylinder 8 below the'piston I0 and with the oil receptacle 6 by valve controlled passages which may be of a known or any suitable character and are not here shown.

The lever mechanism may take variousforms and that here illustrated is of a form particularly adapted for application to a hydraulic lifting jack. It comprises an operating member l5 pivotally connected at IB with the piston I4 of the pump, which constitutes the part to be operated. Operative movement is imparted to the operating member by a lever, or handle, I8, which is preferably s0 connected with the operating member that it will be rigid therewith during the lifterating member, and for actuating the connecting member. able character and in the arrangement shown the operating member i5 is provided at its other end, that is, on that side of the pivotal connection I6 opposite the socket with an enlargement or housing I9 which is rigid therewith and in the present instance is formed integral therewith.' In this housing there is provided a longitudinal guideway 20 which is preferablyv cylindrical in cross section. A longitudinal chamber 2| is arranged in the housing above the guideway 20 and is connectedwith the latter by a longitudinal opening 22 of a width substantially less than the diameter of the guideway 20. Slidably mounted in the guideway 20 is a member 23 with which the fulcrum is plvotally connected and which serves to connect the fulcrum with the operating member. This member is'here shown as a block cylindrical in cross section and is held against transverse movement in its guideway. The fulcrum member may be of any suitable character and, as here shown, it comprises an elongate member 24 pivotally mounted at' its lower end on the base 5, as shown at 25, and having itsupper end bifurcated to provide lugs 23 which extend on opposite sides 4of the guideway 2U and are provided with alined apertures. A pin 21 extends through the apertures in the lugs, through longitudinal slots 28 in the side walls of the guideway 20 and through a transverse opening 29 in the connecting member 23, the pin being held against lengthwise movement Vby snap rings 30. 'Ihus the fulcrum member is connected with'the connecting member for movement therewith and the fulcrum point may be adjusted to any'position between the ends of the slots 28 by the movement of the connecting member in its guideway.

Movement may be imparted to the connecting member or slide block 23 by any suitable means but I prefer an actuating device which can be operated by the movement of the lever with relation to the operating member. When the lever is rotatably connected with the operating member it is desirable that the actuating device shall comprise a rotatable element. In theY construction here illustrated an elongate element 3|, having a' screw threaded portion 32, is rotatably supported in the chamber 2| substantially parallel with the guideway 20, This rotatable element is provided with a portion 32 of reduced diameter which extends through and is supported in an opening in a wall 33 which separates the chamber 2| .from the socket I1, and is held against axial movement by the shoulder formed by the reduced portion thereof and by ahead 34 secured theretoin the socket Mounted on the screw threaded portion of the element 3| is a nut 35, and the slidable member 23 is connected with the nut for movement therewith so that the rotation of the screw will move the member 23 lengthwise of its guidewayl The member 23 may This means may be of any suit- 4 be connected with the nut 35 in any suitable manner and, as here shown, the two parts are formed separate and the slidable member 23 isprovided with a transverse bore 36 having an intermediate portion 31 of reduced diameter. The upper portion of the bore constitutes a socket and the nut 35 has a part 38 rigid therewith and extending into the socket to connect the slidable member with the nut. The part 38 of the nut is secured in the socket by a screw 39 extending through the reduced portion of the bore 36 and threaded into the part 38, the head of the screw being seated in the lower portion of the bore.

That part of the lever 8 which extends into the socket has a hollow inner end portion to 'receive-the head 34 of the rotatable screw 3| and is-provided with slots 4| to embrace studs 42 rigidly secured to the head. Thus by rotating the .lever inthe socket the screw may be rotated and the nut actuated to move the slidable member and the attached end of the fulcrum member lengthwise of the operating member to any position within the range of movement of the slidable member, and the fulcrum member will be retained in its adjusted position by the nut.

\ While I have shown and described one embodiment of my invention I wish it to be understood that I do not desire to be limited to the details thereof as various modifications may occur to a person skilled in the art.

Having Vnow fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A lever mechanism comprising an operating member having means for operatively connecting the same with a part to be Operated, a movable fulcrum, an adjusting device mounted on said member and connected with said fulcrum, a lever connected with said operating member for imparting operative movement to the latter and for movement with relation to said member, and means operable upon said movement of said lever with relation to said operating member to actuate said adjusting device. Y

2. A lever mechanism comprising an operating member having means for operatively connecting the same with apart to be operated, a movable fulcrum, -a movable member supported on said operating member lfor movement lengthwise thereof and'held against movement transversely thereto, means for connecting said movable member with said fulcrum, a lever for imparting movement-to said operating member and rotatable with relation thereto, and means operable upon the rotation of said lever to actuate said movable member.

3. A lever mechanism comprising an operating member having means for operatively connecting the same with a part to be operated, a movable fulcrum, a member slidably supported on said operating member for movement lengthwise thereof and held against movement transversely thereto, means for connecting said slidable member with said fulcrum, a screw rotatably mounted on said operating member, ,means for operatively connecting said screw with said slidable member, a lever for imparting operative movement to said operating member and rotatable with relation thereto, and means for connecting said screw with said lever for rotation thereby.

4. A lever mechanism comprising an operating member having between its ends means for connecting it with a part to be operated and having in one end thereof a socket to receive a lever, said member having adjacent the other end thereof a longitudinal guideway, a member slidably mounted in' said guideway and held againstV transverse movement with relation thereto, a movable fulcrum connected with said slidable member for movement therewith, a device'mounted on said operating member for imparting movement to said slidable member, a lever having -a part to be inserted in said socket and capable of rotation therein, and means for operatively connecting said lever with said movement imparting device.

5. In a lifting mechanism comprising a lifting element and means for actuating said` lifting element including a reciprocatory element, a fulcrum member movably supported on a part of said mechanism, an operating member operatively connected with said reciprocatory element, means for connecting said fulcrum member with said operating member |for movement toward and from said reciprocatory element, a lever for imparting operative movement to said operating member and capable of movement withrelation thereto, and means controlled by said movement of said lever with relation to said operating member for actuating said connecting means.

6. In a lifting mechanism comprising a lifting element, :and means for actuating said lifting element including a reciprocatory element, a fulcrum member movably supported on a part of said mechanism, an operating member operatively connected with said reciprocatory element, means for connecting 'said fulcrum member with said operating member for movement toward and from saidreciprocatory element, a rotary device carried by said operating member for actuating said connecting means, a lever for imparting operative movement to said operating member and rotatable with relation thereto, .and means for connecting said actuating device with said lever for rotation thereby. Y 1 v 7. In a lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element, a fulcrum member :movablyV mounted on a fixed support, an operating member operatively connected with said reciprocatory element, a member slidably mounted on said operating member for movement toward and from said reciprocatory element and pivotally connected with said fulcrum member, a member supported by said operating member for rotation about an axis extending lengthwise of the latter, means actuated by said rotatable member for moving said slidable member toward and from said reciprocatory element and for locking the same in any position within the limits of said movement, and means for actuating said rotatable-member.

8. In a lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element, a fulcrum member movably mounted on a xed support, an operating member operatively connected with said reciprocatory element, a member slidably mounted on said operating member for movement toward and from said reciprocatory element and pivotally connected with said fulcrum member, a member rotatably supported by said operating member and having a spiral part, means for operatively connecting said spiral part with said slidable member to impart sliding movement to the latter, and means for rotating said rotatable member.

9. In a lifting mechanism comprising a lifting element and means lfor Yactuating said lifting element including a reciprocatory element, a fulcrum member movably mounted on a fixed support; an operating member operatively connected with `said'reciprocatory element, a member slid'-4 ably v mounted on said operating member for movement towardand from said reciprocatory element andA pivotally connected with said fulcrum member, a screw rotatably supported by said operating member, a nut on said screw, means for operatively connecting said nut with said slidable member, and means 'for rotating said screw, Y n f 10. In a lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element, a fulcrummember movably mounted on a xed support, an operating member operatively connected with said reciprocatory element, la member slidably mounted on said operating member for movement toward and from said reciprocatory element and pivotally connected with said fulcrum member, a device mounted on said operating 'member for actuating said slidable member, a

lever mounted on said operating member for imparting operative movement thereto and for movement with relation thereto, and means for connecting said actuating device with said lever for operation by the latter.

ll. In a lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element, an operating member pivotally connected with said reciprocatory element and having a socket to receive a lever, a movable fulcrum member, a connecting member `mounted on said operating member for movement lengthwise thereof and pivotally connected with said fulcrum member, a rotatable device for actuating said connecting member, a lever adapted to be inserted in said socket and rotated therein, and means for operatively connecting said lever with said rotatable actuating device. c

12. In a'lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element,v an operating member pivotally connected with said reciprocatory element and having a socket to receive a lever, a movable fulcrum member, a connecting member mounted on said operating member for movement lengthwise thereof and pivotally connected with said fulcrum member, a part connected withl said connecting member for movement therewith and vhaving a screw threaded opening, an actuating member rotatably supported by said operating member and having a screw threaded portion extending into said threaded opening'a lever adapted to be inserted in said socket and operatively connected with said actuating member, said leverbeing rotatable in said socket to rotate said actuating member.

13. In a lifting mechanism comprising a lifting n element and means for actuating said lifting element including a reciprocatory element, an 0perating member pivotally connected between its ends with said reciprocatory member and having a socket in one end thereof and a longitudinal guideway adjacent the other end thereof, a connecting member slidably -mounted in said guide- 14. In a, lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element, an operating member pivotally connected between its ends with said reciprocatory element and having a socket in one end thereof and a longitudinal guideway adjacent the other end thereof, a connecting member slidably mounted in said guideway, a movable fulcrum member connected with said slidable member for movement therewith, a screw threaded member rotatably supported on said operating member and extending lengthwise of said guideway, a nut mounted on said screw threaded member and connected with said slidable member, a lever adapted to be inserted in said socket and rotated therein, and means for connecting said screw threaded member with said lever for rotation thereby,

15. In a lifting mechanism comprising a lifting element and means for actuating said lifting element including a reciprocatory element, an operating member pivotally connected between its ends with said reciprocatory element, having at one end thereof a socket and having at its other end a hollow portion which is provided within the same with a longitudinal guideway, a longitudinal chamber, and a longitudinal opening connecting said chamber with said guideway, a block slidably mounted in said guideway, a fulcrum member pivotally mounted rat one end on a fixed support, and pivotally connected at its other end with said block, a screw rotatably supported in said chamber substantially in line with said socket, a nut on said screw connected with said block, and a lever adapted to be inserted in said socket and vrotated therein, saidV lever and said screw having interengaging parts to operatively connect said lever with said screw.

16. A lever mechanism comprising an operating member having means for operatively connecting the same with a part to be operated and having a tubular portion forming a guideway, a block slidably mounted in said guideway, a movable fulcrum, a pivot pin connecting said fulcrum with said slide block, and means for adjustingV said slide block lengthwise of said guideway.

17. A lever mechanism comprising an operating member having means for operatively connecting the same with a part to be operated and having a tubular portion forming a guideway, a block slidably mounted in said guideway, a movable fulcrum, a pivot pin connecting said fulcrum with said slide block, and operable means carried by said operating member to move said block to and retain the Same in a selected position in said guideway,

18. A lever mechanism comprising an operating member having means for operatively connecting the same with a part to be operated and having a guideway, a block slidably mounted in said guideway, amovable fulcrum pivotally connected with said slide block, and means for adjusting said slide block lengthwise of said guideway including a screw and means for actuating said screw.

19. A lever mechanism comprising an operating member having means for operatively connecting the same with a part to be operated and having a guideway, a block slidably mounted in said guideway, a movable fulcrum pivotally connected with said slide block, a screw rotatably mounted on said operating member and extending substantially parallel to said guideway, a nut on said screw connected with said slidable member, and means for rotating said screw.

20. A lever mechanism comprising an operating member having means whereby it may be connected with a part to be operated and having on one side of said connecting means a housing, a part of which forms a guideway, a member mounted in said guideway for sliding movement toward and from said connecting means, a movable fulcrum connected with said slidable member, and an adjusting device mounted in said housing and operatively connected with said slidable member.

21. A lever mechanism comprising an operating member haidng between its ends means whereby it may be connected with a part to be operated and having a guideway on one side of said connecting means, an actuating device connected with said operating member on the other side of said connecting means, a member mounted in said guideway, held against rotation therein and movable lengthwise thereof, a movable fulcrum, a pivot pin connecting said fulcrum with the member in said guideway, and adjusting means carried by said operating member and connected witlrthe member in said guideway to move the latter lengthwise of said gudeway.

FRANK B. COPELAND.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Rosenberry 1 Apr. 11, 1939 

